This is a great, very unique and different book! I really enjoyed it a lot!
Starters is in a Dystopian were the U.S was infected by a Spore War. Only the young and the elderly were able to get vaccinated before the spores were launched, and all the ages in between died because they were not vaccinated. Now, the young, if they don't have any eldery relatives left, must fend for themselves while the elders live in style.
The only thing the elders don't have are young, able bodies. But technology has made it so that the elders can "rent" out a younger body, for a large price. Callie, is in desperate need of the money. She needs a safe and reliable shelter over her head for her and her sick brother. The only way she can find to make that money is to rent out her body to an elder. But then, when she rents her body things become complicated and Callie gets twisted up in a very dangerous situation!
There are a lot of twists I didn't see coming. The storyline is very unique and really gets you wondering. At the end, I felt like I had to read it again just to grasp what was going on the entire time! It does leave you at quite a big cliff hanger but it says the next book is coming out this winter, so that isn't a very long wait.
If you liked Fever and Wither, or even the Uglies series, you will like this book.